The Flowering Plant and Photosynthesis

The Flowering Plant and Photosynthesis

AIM To name and identify some common Irish trees To identify the parts of a flowering plant To list the function of the flowers, stem, leaves and roots To explain what photosynthesis is and why it is important

Lifecycle of a Flowering Plant

Plants Algae Mosses Ferns Conifers Flowering Plants Seaweed Live in damp places Produce seeds in cones Most advanced type of plant. Include Oak, Ash, Chestnut Trees, Grasses, Cereals (wheat, oats, barley) and flowers (daffodils, tulips, daisies, dandelions)

Main features of flowering plants: Normally divided into roots, stems & leaves Special cells (tissues) allow plants to transport water, minerals & food throughout the plant Produce flowers (not always brightly coloured) Reproduce using seeds Seeds are enclsed in fruits

Introduction to Flowering The Root The Stem The Leaves The Buds The Flowers Plants

The Roots The roots hold (anchor) the plants in the ground and take up nutrients and water. Some roots are swollen and contain food e.g carrots Roots grow down because of gravity. Nutrients taken up by roots include nitrogen, phosphorus & potassium

The Stem Stems support & hold plants upright so they can obtain sunlight. Stems also carry food and water to all parts of the plant. The stem moves and grows to keep leaves turned towards light. Buds = potential growth point for new leaves or flowers

The Leaf The leaves give out or transpire water. Green plants are able to make their own food in a process called photosynthesis. When sunlight is present the leaves use light energy and take in carbon dioxide which is converted into sugars and starches which can be stored. Oxygen passes back to the atmosphere through the stomata. F:\Midleton CBS\leaffactories.pdf Leaf Blade Veins Petiole Midrib

Functions of the Parts of a Plant Root Stem Leaf Flower 1 To anchor the plant To hold up the leaves, flowers and fruit To make food (photosynthesi s) To make seeds during reproduction 2 3 To absorb water and minerals Some plants store food e.g. carrots To allow transport of water and minerals from the roots and food up and down To allow the plant to lose water vapour To allow exchange of gases

Photosynthesis

Photosynthesis Photosynthesis uses the energy of light to make the sugar, glucose. A general equation for photosynthesis is: 6CO 2 + 6H 2 O + light C 6 H 12 O 6 + 6O 2 Carbon Dioxide + Water + Light Energy --> Glucose + Oxygen F:\Midleton CBS\Howdoplantsmakefood.pdf

Importance of Photosynthesis 1. It produces glucose needed by both plants and animals 2. It produces oxygen gas needed for respiration 3. It removes CO 2 fom the air.

Water Transport Water carried in tiny tubes (veins) through plant Stomata (tiny pores) underneath leaves allow water evaporate into air Transpiration is the loss of water vapour from a plant The transpiration stream is a flow of water from the roots to the leaves of a plant Water (soil) Roots Stem Leaves Stomata Air

Factors affecting rate of transpiration 1. Sunlight: causes stomata to open increases transpiration 2. Wind: removes water vapour from leaf, on windy day increased transpiration 3. Soil water: the greater the amount of soil water, the greater the transpiration 4. Humidity: is the amount of water vapour in the air. The less water vapour there is in the air (less humid), the greater the rate of transpiration

Functions of Transpiration Supplies water to leaves for photosynthesis Supplies minerals to leaves minerals dissolved in water enter throught the roots Helps cool plants (like sweating cools the human body)

Mineral Transport Nitrogen, Phosphorus, Potassium (& many others) are dissolved in water in soil Plants need minerals to grow A lack of minerals plants lose green colour & do not grow Fertilisers added to oil to add minerals Food Transport Plants have 2 types of transport/vascular tissue 1. XYLEM 2. PHLOEM They both carry liquid around plant They form continuous tubes in the plant, i.e. they re found in roots, stems, leaves and flowers

Xylem Carries water and dissolved minerals from roots to leaves Often forms hard tissue, e.g. forms wood in trees Phloem Carries food (sucrose a sugar) in plants Phloem is a softer tissue than Xylem